2005 · ソースブック（プレイを拡張するルール／オプション）
The Ultimate Metamorph
A HERO System sourcebook for creating and playing shape-changing characters across superhero, horror, science fiction, and fantasy settings. It covers metamorphic character types and provides expanded rules for powers such as Duplication, Density Increase, Multiform, Shape Shift, and Shrinking. The book includes nearly 300 customizable metamorphic abilities, genre-based sample characters, plot hooks, a bestiary of shapeshifting creatures, and rules for adventures in the microscopic Microverse and gigantic Macroverse.
スキルベース（スキルを購入または獲得）ポイント制（ポイントを割り振ってスキルや能力を得る）ダイス（主にd6）
ゲーム情報（人数、プレイ時間、対象年齢、クレジット）の出典：BoardGameGeek。